Up to now, studies on inflammation in PD have mainly focused on the detection of pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-6, and IFN-γ, and anti-inflammatory cytokines, such as IL-10 and TGF-β, in the cerebrospinal fluid and peripheral blood of PD patients. The gene discussed is IFNG; the disease is Parkinson disease.